One of the great joys of my life is that I get to spend time with some of the world's foremost experts and builders and call it work.

While I don't have a "podcast" in the traditional sense—I don't want to turn something fun into a business—I have recently decided that I'd like to try to record and share the insights from some of these natural conversations so that everyone can benefit from them in the way that I have.

In that vein, last week, I got together with a friend—Dr. Robert Waldinger—and spent two hours in a deep and wide-ranging discussion.

I had a team come out and record it, so will release a full video in the coming weeks, but today, I want to share a few of the most impactful takeaways from our conversation.

For those of you who don't know him, Dr. Waldinger is the director of the Harvard Study of Adult Development, which is the longest-running study on adult life, health, and happiness in the world. It tracked the lives of 700+ original participants and 1,300+ descendants over 85 years. His Ted Talk has been viewed nearly 50 million times and his book, The Good Life, was an instant New York Times best-seller.

Here are 5 lessons from my conversation with a world-renowned happiness expert...

Note: If sharing insights, audio, and video from these conversations is something you're interested in seeing me do more of in the future, reply YES to this email.

Lesson 1: Relationship Satisfaction Impacts Health

I asked Dr. Waldinger about the most shocking finding of the Harvard Study.

His response:

"Relationship satisfaction at age 50 was the single greatest predictor of physical health at age 80."

This bears repeating:

Relationship satisfaction was a more effective predictor of health at age 80 than cholesterol, blood pressure, or any other health marker tracked by the study.

The strength and quality of your relationships has a direct and powerful impact on your physical health as you age.

Lesson 2: Loneliness Kills (& It's More Prevalent Than Ever)

In 2023, the U.S. Surgeon General Vivek Murthy released a report, entitled Our Epidemic of Loneliness & Isolation, that sounded the alarm on a number of scary trends in society.

A few statistics that jumped out to me:

• The amount of time teenagers are spending in person with their friends is down 70% over the last two decades.
• 60% of adults say they don't feel very connected to others.
• The number of men who say they have zero close friends is up 5x since 1990 (15% vs. 3%).

And unfortunately, loneliness kills.

A number of scientific studies—including Dr. Waldinger's Harvard Study—have found that the health impact of loneliness is quite dire.

Chronic loneliness has been found to increase dementia risk by up to 50%.

This image, cited in the Surgeon General's report, shows that a lack of social connection is worse for your health than tobacco and alcohol abuse, obesity, and more.

The epidemic of loneliness needs our attention.

Lesson 3: Make "Social Fitness" a Priority

To fight back against loneliness, Dr. Waldinger suggests that we all need to make "social fitness" a priority.

His idea is that our social health should be thought of in the same manner as our physical health—that it's the result of tiny daily actions that compound over long periods of time.

This characterization resonates deeply—make your social health a part of your daily routines:

• When you think something nice about someone, let them know right then.
• Tell your partner one thing you appreciate about them every single day.
• Reach out to that friend and catch up.
• Plan that dinner or group gathering.
• Go on that trip with your old friends.

Your daily social health actions compound. Build your Social Fitness.

Lesson 4: Check Your Energy to Improve Your Life

When discussing strategies for improving relationship satisfaction and overall happiness, Dr. Waldinger offered an energy hack that I love:

After you consume a piece of content, assess your energy level. Did consuming that piece of content make you feel energized or drained?

If the latter, you may want to reduce the amount of that type of content that you consume.

I believe the same hack can apply to relationships:

Check your energy level after spending time with someone. Do you feel energized or drained?

Spend more time with your energy creators and less time with your energy drainers. Your life will improve.

Lesson 5: Ambivalent Relationships are the Most Toxic

I asked Dr. Waldinger about what they found in their research on toxic relationships and how their study participants navigated them.

He pointed to a fascinating reality:

Ambivalent relationships—those that are sometimes supportive and sometimes demeaning—are actually worse for your health than purely demeaning relationships.

A variety of studies on humans and animals have shown that ambivalent relationships have sharper negative health consequences than purely toxic ones.

His (and my) explanation was that the relationships that are inconsistent leave a person exposed: They open up due to the love and support, allowing the demeaning behavior to cut deeper.

Audit your relationships. Consider those that may have ambivalent characteristics—people who are supportive at times, but deeply demeaning at others. It may be time to reduce the energy given to these people.

Relationships Are Everything

Anthropologist Robin Dunbar, most famous for his research on the cognitive limit to the number of stable social relationships a single person can maintain, recently commented on the body of research around relationships and health:

"By far the biggest medical surprise of the past decade has been the extraordinary number of studies showing that the single biggest predictor of your psychological and physical health and wellbeing is simply the number and quality of close friendships you have."

Relationships are, quite literally, everything.

Hopefully the insights from my conversation with Dr. Robert Waldinger shine a light on their importance—and hopefully you take a few tiny actions that improve your Social Fitness in the days and weeks ahead.

Invest in your relationships—they will pay dividends in all areas of your life for many years to come.

Note: The full video and audio recording of our conversation will be available in the coming weeks. Stay tuned. If sharing insights, audio, and video from these conversations is something you're interested in seeing me do more of in the future, reply YES to this email.